South Korea's Jang Na-ra is known throughout Asia as a singer and an actress. Add something else to her resume: compulsive gamer.

On a recent Korean talk show, Jang revealed that she fell in love with hanafuda—a Japanese card that should be familiar to all Nintendo fans. Whether it was playing with her brother or with her manager, Jang fell hard for hanafuda. She played it for days on end. Before she fell asleep, she'd see hanafuda on her bedroom ceiling.

Worried that her hanafuda gaming was starting to become a problem, Jang found a new hobby: video games. That didn't turn out much better.

"Then, I just played video games without bathing, sleeping, or eating," she said. So her compulsive hanafuda playing was swapped with compulsive gaming—she didn't specify the game.

Jang gamed so much, she claimed she injured herself. "One day, my thumb started to swell and bruise, so I ultimately had to get it operated on."